Collapsible arch-form.



G. A. 'COMPT-ON. v COLLAPSIBLE ARCH FORM.

APPLICATION FILED NOV. 5. 19m.

Patented Feb. 11, 1919.

2 SHEETS-$HEET I.

G. A. COMPTON.

COLLAPSIBLE ARCH FORM. APPLICATION F1120 NOV- 5, 1917.

1,294,239 I Patented Feb. 11,1919.

2 SHEETS-SHEET 2.

flVVE/Y TOE 6/6/90 '14. Compfon 5r ///5 A770E/YEX5' 20 wm mm GLENN A. COMPTON, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR OF ONE-HALF TO GUY B. ELWOOD, 0F MINNEAPOLIS, MINNESOTA.

Specification of Letters Patent.

COLLAPSIBLE ARCH-FORM.

Patented Feb. 11, 1919.

Application filed November 5, 1917. Serial No. 200,228.

To all whom it may concern:

Be it known that I, GLENN A. COMPTON, a citizen of the United States, residing at Minneapolis, in the county of Hennepin and State'of Minnesota, have invented certain new and useful Improvements in Collapsible Arch-Forms; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appert-ains 'to make and use the same.

My invention relates to improvements in collapsible arch forms, especially adapted for use in the construction of concrete bridges, culverts, conduits, and the like. To the above end, generally stated, the invention consists of the novel devices and combinations of devices hereinafter described and defined in the claims.

In the accompanying drawings, which illustrate the invention, like characters indicate like parts throughout the several VIBWS.

Referring to the drawings,

Figure 1 is an end elevation of the invention;

Fig. 2 is a fragmentary longitudinal central section;

Fig. 3 is a perspective View of one of the arch bars; and

Fig. 4 is a view corresponding to Fig. 1, but illustrating a modified form of arch bar.

The numeral 5 indicates a pair of laterally spaced longitudinal sills, in the form Pivoted' to and between the side walls of each bearing bracket 7 is a tripping abutment 9 and a gravity-held hook-like latch 10 located, the former below the web 8 and the latter above the same. The tripping abutment 9 is in the form of a bell crank with its long arm normally project- 'ing downward and its short arm extending horizontally and provided withan upwardly projecting retaining lug 11, which is located in the same plane with the overlying hook end of the latch 10. It is important to note that the short arms ofthe tripping abutments 9 and the free ends of the latches 10 all project in the same direction and that they also normally-project beyond the adjacent edges of the bearing bracket 7.

Looks 12 are provided for holding the tripping abutmen-ts 9 in operative positions and each thereof is arranged to engage the long arm of the respective tripping abutments 9 to prevent downward movement of the short arm thereof. These locks 12 are secured to pivot pins 13, mounted in the side walls of the bearing brackets 7, and which pivot pins have secured to one of their ends normally upwardly projecting arms 1 1 to the free ends of which are att-ached cables 15, by which said locks may be operated at a distant point to release the trip-ping abutments 9. It will be noted that the cables 15 all extend in the same direction, so that they may be simultaneously operated.

Supported from each laterally spaced pair of tripping abutments 9, is a segmental arch bar 16, which extends transversely of the sills 5/ The ends of eachj arch bar 16 are rigidly connected by a flat bar 17 that is set edgewise and secured to one side of said arch bar. The arch bars 16 are of such size as to span the respective pair of bearing brackets 7 with the bars 17 extending outside of said brackets and resting on the short arms of the tripping abutments 9. It will be noted that the latches 10 are turned over the upper edges of the bar 17 and, together with the retaining lugs on the tripping abu'tments 9, hold said bars 17 against the bearing brackets 7 and in upright positions. Formed in the upper and lower edges of the bars 17, are notches 18, with which the tripping abutments 9 and latches 10 interlock to hold the arch bars 1 6 properly positioned over the sills 5.

At the crown of each arch bar 16, is formed a pair of oppositely extended seats 19 and, at the lower ends thereof, are seats 20 and beveled shoulders 21. The purpose of these seats 19 and 20 and shoulders 21 will presently appear.

Loosely supported on the crown of the arch bar 16, is a ridge plate 22, having at its longitudinal edges upturned flanges.

This ridge plate 22, at its longitudinal center, is bent upward, so that only its longiplate comprising a plurality of slats 23'and a slat 24. Each slat 23 has, at itsilongltir dinaledg'es', inwardly projecting flanges 25, one of which is bent -:inwardly f-i30"g1V8" it'a-r hook shape. On the upper longitudinal ,edges"ofthe slats -24, are inturned hookl-ike flanges 26, adaptedto engage the bev- -;yeled shoulders 21 and support said slats therefrom with their lower longitudinal edges-overlapping the vertical flanges of the-i" I *wardly pro ect1ng fingers 30from which the sills 5, i

- H Thelowermost-opposite pair" of slats 23 is supported directly on the flanges 260i the slat-s524-and the'other of'said slats 23 --are supported,-the one upon the other :with' I 'theupper-gfi-anges of the uppermost oppo- -'1-Site pair-of saidslats interlocked with the fianges'of: the-ridge plate- 22. The inter -lockmg of the uppermost pair of slats 23" 25v-with the flanges of the ridgplate 22 assists --in "supporting said slats from the ridge plate and, at-the same time, permits/all of :the slats 23 to move toward the center of the arch, upon the collapsing of the form.

-- To -prevent cement from filling in 'on the" ridge plate 22 and thereby make it diflicult -to remove-the same, and which would also .i prevent the slats-23 from moving toward the center of the arch, upon the collapsing of the form, I provide a cover plate 27 This F i cover plate 27 overlaps the joints-between 'theridge plate 22and slats23, and is super ported-in partrfrom the ridge plate 22 by short legs 28, which directly engage said' g 40' ridge plate. i V

:In setting up the collapsible form, the sills x5 are first positioned on the sills 6. Thearch-bars 16 are then mounted on the trip-v aping, abutments'9 with the cables 15 extending OlliISldQDlf the=space to be occupied by V the archvaThe last operation is to hang the slats 24 from the shoulders 21yand place-v the ridge plate 22 and slatss24in position ongthe arch bar 16. It will thus be seen wannabe am ma be very quickly set up 1, in-position to support the concrete or other materials?fromtwhich the arch is to be r formed,

brackets .plate 22, :slats23 and coverplate 27 are adhere to the arch, they may be readily re .I OYBd. With themfqrm collapsed,the same ieachaich bar 16, a substantially rectangular arch or opening may be formed. ,These angle" 'brackets 29 have their lower ends loosely restingsin the seats 20 and their upper ends removably mounted in the seats 19. The ridge plate eaned-r;- slats'f23 are supported on the brackets29 in "the same manner"as-on thearch bars 16, with the exceptionthat the vertical membersoit' the brackets 29 have short'upwardly and out:-

brackets 29 by the depending flanges on the,

outer longitudinal edges of the overlying horizontal slats23. *By bending one of the flanges-of each slat -23 inward, r'said slats are permitted-to closely follow the-outline 'of either of the arches shown in Figs; 1.

"andip' 1 What I claim is 1. A collapsible'form for use" in the construction of arches? including a *tripping abutment, and an arch bar supported on the tripping abutment, said tripping abutment arranged to move fromunder the arch bar to permit the same to move straight down.

2. A collapsible f0rm-for-use'in the construction of ;archescomprising tripping;

abutments, arch bars sup-ported on the vtripping 'abutments, said, trip-plng abutments having interlocking engagement; with the arch bars ;for holding ;the same against transverse movement with respect to *the arch, and side; plates supported'on the arch bars. l

3.{A collapsible form tor use the construction of archesinjcluding a tripping abutment,an arch bar supported on" the trlppmgabutment', and means forreleasing the tripping abutment,- said tripping abutment arranged to move from under the arch bar to'permlt the same to move straight .down. r V 4. A collapsible form for use in theconstruction of arches "including a' tripping v i a abutment, an archbar supported onthe tripa After the archis completed and the mate-; n=rialsfrom which it is constructed properly setg the formmay be removed by first draw- I ing on the cables 15 to cause thecollapsethereof. This movement of the cables 15 releases the tripping abutments .9 and permits-the'arch bar 16 to drop'straight down, i-I-w with respect to the formed arch, bearing and slats 24. In the downward xmovementiof 'the arch bar 16, the ridge said tripping abutment arranged to move permit theisame from under the arch bar to to move-straight down. i

1 515A collapsible form tor use in the construction of arches ,rcomprising tripping abutments, arch bars supported on the tripping abutments, latches for holding the; arch bars in upright positions-"on the tripping abutments, means for releasin the-tripping abutments to permit the arch bars to lower and side plates supported on the arch bars.

6. A collapsible form for use in the construction of arches comprising tripping abutments, arch bars supported on the trip ping abutments,latches for holdingthe arch bars in upright positions on the tripping abutments, said trippin abutments and latches having interloc 'ng engagement with the arch bars to hold the same against transverse movement with respect to the arch, means for releasing the tripping abutments to permit the arch bars to lower, and side plates supported on the arch bars.

7. A collapsible form for use in the construction of arches comprising bearing brackets having tripping abutments, arch bars supported on the tripping abutments and against the bearing brackets, latches for holding the arch bars in upright positions on the tripping abutments and against the bearing brackets, means for releasing the tripping abutments to permit the arch bars to lower, and side plates supported on the arch bars.

8. A collapsible form for use in the con struction of arches comprising bearing brackets having tripping abutments, arch bars supported on the tripping abutments and against the bearing brackets, gravityheld latches for holding the arch bars in upright positions on the tripping abutments and against the bearing brackets, means for releasing the tripping abutments to permit the arch bars to lower and move away from the latches, and side plates supported on the arch bars.

9. A collapsible form for use in the construction of arche comprising tripping abutments, arch bars supported on the tripping abutments, means for releasing the tripping abutments to permit the arch bars to lower, a ridge plate sup orted on the arch bars, side plates supports on the arch bars and interlocked with the ridge plate with freedom to move toward the center of the arch during the collapsing of the form, and a cover plate extending over the ridge plate and interlocked edges of the side plate.

10. A collapsible form for use in the c0nstruction of arches comprising a pair of longitudinal sills, bearing brackets on the sills and having tripping abutments, arch bars supported on the tripping abutments, said arch bars having at their lower extremities shoulders, side plates made up of a plurality of slats, the lowermost pair of which are hung from the shoulders on the arch bars and overlap the sills, means for releasing the tripping abutments to permit the arch bars to lower with respect to the side plates, the other of said side plates being supported on the lowermost pair of side plates with freedom to move toward the center of the arch during the collapsing of the form.

11. A collapsible form for use in the construction of arches comprising a pair of arch bars, and side plates on the arch bars made up of a plurality of slats having flanges at their longitudinal edges upon which the slats may rest, the one upon the other, one of the flanges of the abutting slats being bent inward, whereby the slats may be laid in the same plane or on a curve.

12. A collapsible form for use in the construction of arches comprising a segmental arch bar, and angle brackets cletachably ap plied to the arch bar,

13. A collapsible form for use in the construction of arches including an arch mem her, and angle brackets detachably applied to the arch member.

In testimony whereof I aflix my signature in presence of two witnesses.

GLENN A. COMPTON.

Witnesses:

CLARA DEMAREST, HARRY D. KILGORE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

